Java excel重写单元格

Question

美好的一天！我可以从Excel读取数据或创建新文档进行录制。但我无法从我们的数据中打开现有文档以了解单元格中的更改。请帮助。

import jxl.Workbook;
import jxl.read.biff.BiffException;
import jxl.write.*;
import java.io.File;
import java.io.IOException;

public class testExcel {
    public static void main(String[] args) throws IOException, BiffException,    WriteException {
        File file = new File("D:\\testE.xls");
        WritableWorkbook workbook = Workbook.createWorkbook(file);
        WritableSheet s = workbook.createSheet("Sheet1", 0);
        WritableFont wf = new WritableFont(WritableFont.ARIAL, 10, WritableFont.BOLD);
        WritableCellFormat cf = new WritableCellFormat(wf);
        Label l = new Label(0, 0, "new", cf);
        s.addCell(l);
        workbook.write();
        workbook.close();
    }
}

然后创建一个新文档，但我需要打开一个现有文档并更改一些单元格